Nanoparticles may boost stability, bioavailability of resveratrol

Simple and economically affordable nano-carrier systems may protect resveratrol from photodegradation and aid absorption across the intestinal barrier, says a new study from Portugal.

Scientists from the University of Porto report that solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) could both be successful carrier systems for resveratrol supplements or nutraceuticals.

“SLNs and NLCs are composed of biodegradable and biocompatible lipids recognized as safe by Food and Drug Administration, which can be loaded with the lipophilic and poorly soluble resveratrol, for further use in food supplements,” ​the wrote in Nutrients​​. “Moreover, the preparation of lipid nanoparticles is very simple, rapid and economically affordable for food industry scale up.”​

Resveratrol​

Interest in the resveratrol, a polyphenol often touted as the bioactive compound in grapes and red wine, exploded in 2003 when research from David Sinclair and his team from Harvard reported that resveratrol was able to increase the lifespan of yeast cells. The research, published in Nature​, was greeted with international media fanfare and ignited flames of hope for an anti-ageing pill.

According to Sinclair’s findings, resveratrol could activate a gene called sirtuin1 (Sirt1 – the yeast equivalent was Sir2), which is also activated during calorie restriction in various species, including monkeys.

Despite the interest in the compound, oral delivery of resveratrol can be a challenge, wrote the Porto-based scientists, because of its low solubility, rapid degradation and extensive metabolism. In addition, trans-resveratrol, the biologically active isomer, is highly sensitive to light and will quickly convert to the cis (and less biologically active) form.

Various strategies have been employed to protect resveratrol and boost absorption, and the new paper describes the potential of two nanosystems for use in supplements and functional foods and beverages.

SLNs were prepared using solid lipid cetyl palmitate in water, while NLCs were prepared using cetyl palmitate and liquid lipid miglyol-812. Resveratrol entrapment efficiency was 80%, “suggesting they are suitable for resveratrol oral delivery”​, said the researchers.

The nano-systems also showed good protection against photodegradation of the resveratrol, they added.

Additional studies that mimicked gastrointestinal conditions indicated that the NLCs led to increased intestinal permeability of resveratrol, while the SLNs did not impair resveratrol absorption.

In addition, the data indicated that the products should be recommended to be consumed at meal time, because this would further increase intestinal permeability due to the presence of fed-state intestinal juices.

“SLNs and NLCs were developed and validated for trans-resveratrol protection, stabilization and intestinal permeability. Both lipid nanoparticles seem to be compatible and adequate for resveratrol delivery after oral administration, representing a promising strategy for enhancing its ​in vivo efficacy,” ​they concluded.